1. Technical Field
The present invention relates to a semiconductor device, a method for manufacturing the semiconductor device, a circuit board, and an electronic instrument.
2. Related Art
Recently, electronic parts such as semiconductor devices, which are installed in an electronic instrument, have been downsized in electronic instruments such as a mobile phone, a notebook model personal computer, or a PDA (Personal Data Assistant), with the demand for miniaturization and weight reduction. Under such circumstances, a proposal has been made regarding a three-dimensional packaging technology with respect to the semiconductor device. The three-dimensional packaging technology is for stacking semiconductor devices which have functions similar to one another. In addition, the three-dimensional packaging technology may be for stacking semiconductor devices which have functions different from one another. More particularly, disclosure is made in JP-A-2003-282819 about a technology for packaging a plurality of semiconductor devices on a substrate, as an art. In the art, a plurality of semiconductor devices each of which has a feedthrough electrode is stacked, and the semiconductor device of the bottom layer is packaged on an interposer substrate. After that, relocation and rerouting are performed in order to package a plurality of semiconductor devices on the substrate.
However, it is desired that a layered product of semiconductor devices which are packaged on the substrate be small and thin. In order to achieve this, it is necessary to perform further improvement.